DE3720311A1 - Chemically frosting glassware - Google Patents

Abstract

Chemical frosting of glassware, esp. glass lamps, is carried out by continuously passing the glass articles through a sealed tunnel in which they are subjected sequentially to spray cleaning with a hydrofluoric acid-based soln., draining, frosting by passage through a vertical film of a soln. based on hydrofluoric and hydrochloric acids, draining, neutralisation by water spraying, and rinsing opt. by water spraying.

Description

The invention relates to the chemical matting or satinizing of Glassware, in particular lamps and in general all sodium sili kat glasses.

The matting is usually treated by immersing delenden objects in a bath of variable composition, where Hydrofluoric acid is one of the basic substances of the bath, or by Exposure to an acid on fluorides is generated.

For certain applications, however, the matting is done with the help made by an injector who moves the selected solution onto or into the sprayed treating pieces.

In all cases, the mechanization of these processes leads to Use of specific accessories for the pieces to be treated (Carriers, injectors) that take up a considerable amount of inter-serial time expresses as long as a treatment does not refer to comparable articles is fit. The provision of the accessories also leads to considerable Chen additional costs.

Finally, treatment can be done manually if the objects are different or of a small series.

Furthermore, the matting often involves washing them with an acidic or alkaline solution. According to A first way of working is using hydrofluoric acid  attacked superficially, after which the pieces are rinsed around the remove this treatment evoked film.

Another way of working is just a simple degreasing of the pieces made.

After all, matting is always followed by rinsing.

The object of the invention is to provide a method which continuous treatment of articles of all shapes and sizes in consecutive order and number, as well as with inner ones or outer decorative masks are provided or not, where an intimate, homogeneous contact on the entire surface to be treated is ensured with the matting solution.

The invention therefore relates to a method for chemical Matting glassware, especially lamps, characterized in that is that one continuously seals the objects to be treated Lets pass through tunnels and there one after the other as they pass cleaning by spraying on a solution based on fluorwas hydrochloric acid, followed by draining, then matting by covering with a suitable solution based on fluorine water hydrochloric acid of the surfaces to be treated vertical liquid films that are traversed by the objects, ge follows draining and then neutralizing by ver spraying water, followed by rinsing also by spraying Subject to water.

To ensure an even attack from inner parts of the objects allow only one opening in the lower part or even an opening have a small diameter in the upper part and a considerable height, is preferably covering from a spraying of the matting solution accompanied, especially against the objects from bottom to top or from bottom up and top down.

The invention further relates to a device for through implementation of the process, which is characterized in that it consists of four successive autonomous units for cleaning, matting, neutra lisen or rinsing is formed, which is due to dense sluice sen are connected and each have a tight outer shell, the with means of access to the interior, a horizontal conveyor with a  Ribbon with stitches, which is arranged independently in the interior of the jacket is that it forms a conveyor path with the belts of the other units, of the passage of the objects to be treated in a continuous manner through the successive four units ensures means to Spray and / or cover that suitably arranged inside the jacket net, a lock floor under the coat for recovery and Removed or recycled from the unit under consideration Liquids and protective curtains at the entrance or exit of the viewed Has unit, the units for cleaning, matting and rinsing are provided on the side with a storage / recycling container the means for spraying and / or covering are connected, means for loading and unloading objects to be treated at each end of the successive units are provided.

Further embodiments of the invention are the following Be spelling and the claims.

The invention is illustrated below in the Illustrated embodiment illustrated.

Fig. 1 shows schematically from above a device for chemical dulling of glassware,

Fig. 2 shows a side view of the device of Fig. 1,

FIG. 3 shows a vertical section along the line III-III of the device from FIG. 1.

The device shown generally in FIGS. 1 and 2 comprises a sequence of four autonomous treatment units arranged one behind the other, namely a cleaning unit 1 for the objects to be treated, a matting unit 2 , a neutralizing unit 3 and finally a rinsing unit 4 .

Each unit comprises a closed jacket, which forms a sealed tunnel through which the objects to be treated pass. For this purpose, each unit, apart from the last one, has its own horizontal conveyor 5 , which is provided with a mesh with an increased percentage of gaps and is made of a material that resists chemical attacks.

The closed shell of each unit includes two end covers 6 and 7 and two central covers 8 and 9 which are movably mounted to allow access to the interior of each unit for setup, maintenance, etc.

At the connection between two units, a fixed, tight lock 10 is arranged at the level of the feet of the frame which carries the device.

In order to ensure a good transfer of objects, especially those of small diameter or dimensions from a band 5 to a subsequent band, it is advantageous to provide a small intermediate active roller 11 .

At both ends of the device, a fixed cover hood 12 is arranged, which are provided at the entrance and at the exit of the treatment tunnel with groups of suction air-generating electric fans 13 in order to produce a slight negative pressure inside the cover hoods 12 and therefore a possible escape of Prevent liquids at both ends, the suction units being connected to the suction lips, which are arranged at the location of the outer ends of the hoods 12 .

The loading of the tunnel is carried out by a conveyor 14 with a horizontal belt, while the discharge is carried out by a conveyor 15 , which forms the belt of the unit 4 and a return of 180 ° in such a way that the manual removal of objects at the loading height by the same personnel as well as the return of possible carriers for the objects, the return loop for these carriers being closed due to a horizontal roller conveyor 15 which connects the end of the removal conveyor 15 to the loading belt 14 .

The rinsing unit 1 comprises a double spray arm 17 a , 17 b for spraying from above and below, which is equipped with calibrated full cone nozzles 18 . The upper part 17 a of the double spray arm projects beyond the band 5 , which itself runs between two side protective walls 19 , while the lower part 17 b of the double spray arm is arranged between the upper run and the lower run of the jacket 5 , the nozzles 18 of the two arms 17 a , 17 b form two opposing groups.

The unit 1 comprises in the conveying direction slightly before the double spray arm 17 a , 17 b another spray arm 20 a , 20 b , which is arranged in the same way, but with the upper part 20 a calibrated full cone nozzles and the lower part 20 b calibrated flat jet nozzles having.

The double spray arms are supplied from a reservoir 21 for cleaning bath, which is arranged on the side of the unit 1 , via appropriate lines, valves and filters.

The return of the cleaning bath is ensured by a lock floor 22 for collecting solutions, which is arranged under the unit 1 and is connected to the storage container 21 .

The latter is with lines for feeding components the cleaning bath and with control and regulating devices in particular to measure the specific resistance of this bath.

A solution of hydrogen fluoride is preferably used acid that is diluted to 0.5 to 5%.

Finally, the unit 1 is provided with a protective curtain 23 in the area of the fixed protective hoods 6 and 7 .

The matting unit 2 comprises devices for uniformly covering the surface of the objects to be treated.

These devices are formed, for example, by four horizontal trickle channels 24 , which are arranged transversely to the tunnel for carrying out the objects and ensure the formation of a continuous vertical film of matting solution. The channels 24 are completed by upper and lower spray arms (not shown) equipped with calibrated full cone and flat jet nozzles in the same way as the spray arms of unit 1 .

The channels 24 and the spray arms are supplied by a reservoir 25 for matting solution, which is arranged next to the unit 2 , with corresponding lines, valves and filters are provided.

The return of matting bath is ensured by a lock bottom 26 for collecting solutions, which is arranged under the unit 2 and is connected to the reservoir 25 .

The latter is with lines for feeding the components of the Mattierbades and provided with control and regulation facilities therefor.

Hydrogen fluoride is preferably used as the matting bath acid in a concentration of 40 to 70% together with a large one Excess ammonium bifluoride at ambient temperature or a commer currently available matting agent in a hydrochloric acid environment.

Finally, the unit 2 is provided with a protective curtain 23 in the area of the fixed protective hoods 6 and 7 .

The neutralization unit 3 comprises essentially upper and lower spray arms, which are seen with calibrated full cone and flat jet nozzles, the spray arms being arranged in a similar manner to those of the unit 1 .

The first two spray arms 27 ( Fig. 1), which pass through the objects in the unit 3 , are supplied with an alkaline solution from a suitable circuit 28 comprising a pump, solenoid valve, filter and pressure switch.

The objects then pass through upper and lower spray arms 29 which are supplied with rinsing water which is recovered in the last unit 4 via a line 30 .

A lock floor 31 is provided under the unit 3 for collecting and removing waste water for treatment.

The unit 3 further comprises ( FIG. 2) a protective curtain 23 in the area of the fixed protective hoods 6 and 7 .

The rinsing unit 4 comprises a first group 32 of three upper and lower spray arms which are provided with calibrated full cone nozzles and are supplied by a pump 33 which is immersed in a storage container 34 which is arranged laterally to the unit 4 . The Vorratsbe container 23 contains water at a controlled temperature.

A lock bottom 35 is arranged under the unit 4 and enables the water to be returned to the reservoir 34 .

Downstream of the spray arms 32 there is also a double spray arm 36 with an upper and a lower part, which are equipped with calibrated full cone nozzles and are supplied with hot water, which comes from a source other than the reservoir 34 , via a suitable line 37 . The various spray arms 32, 36 are arranged in a similar manner to those of the unit 3 .

The unit 4 further comprises a protective curtain 23 in the area of the fixed protective hoods 6 and 7 .

Furthermore, an electrical control cabinet 38 is provided for controlling and checking the device.

Objects of all shapes and dimensions, in different The sequence and the number of successive sequences are determined by the device treated, the objects with inner or outer decorative masks (Protective masses) can be provided.  

The objects travel continuously along the continuous and sealed tunnel formed by the four units 1 to 4 , where they are successively subjected to cleaning, matting by waterfall-like sprinkling, neutralization and finally rinsing.

The objects are placed directly on the belt 14 or arranged in suitable charging baskets which are designed such that they do not hinder the spraying from above or from below.

The objects and / or baskets are easily transported on a subsequent belt 5 and finally on the conveyor 15 without stopping along the length of the tunnel.

The cleaning in unit 1 serves to prepare the surface of the objects for the subsequent matting. The duration of this process, which is carried out at ambient temperature, is in the order of 15 to 40 seconds and is a function of the type of nozzles 18 selected , the type of glass to be treated and the concentration of hydrofluoric acid in the solution.

The first double spray arm 17 a , 17 b ensures contact with low mechanical action, which enables the treatment of objects provided with protective compositions and this in a non-destructive manner, while the other double arm 20 a , 20 b ensures intensive action, which is suitable for developing the entirety of the preparatory effects sought. The two double spray arms can optionally be operated.

The preparatory effects of cleaning have three goals:

• - the classic effect of degreasing / washing, which the use favored effective pressure;
• - the effect of the superficial solution of the glass skin, which is not only removes disruptive soiling, but also allows the removal of hererogenic skin, which di verse thermoforming processes in glassware; the Zer This skin disorder is essential to get an equal moderate matting (even attack) and required one although reduced mechanical impact of spray jets;
• - A surface-active effect that the subsequent wetting of the be acted surfaces relieved by the matting solution. These Effect results from the chemical action of the flushing agent  means that takes place especially during draining, the follows cleaning. The duration of draining is a function of same parameters as that of cleaning; the lower value will fixed by the construction so that an excessive Mi prevention of the different baths (splashing, entraining) becomes.

The matting carried out in unit 2 is carried out by uniformly sprinkling or covering the surfaces, that is to say by intimate and homogeneous contact (for a sufficient duration as a function of the bath type used) of the treated articles and the active solution.

This is realized in the form of a sequence of liquid films (channels 24 ) that pass through the pieces to be treated. The amount chosen makes it possible to carry out the appropriate chemical attack by avoiding any risk of mechanical action which would be likely to change the decorative masks due to the inherent wear and tear of the bath used due to its considerable task.

This facility, which is excellent for matting exterior surfaces Chen is suitable, does not allow even attack on the inner parts of Objects that have no opening in the upper area, which is why in the lower area Part of a spray arm is provided, the si matting of inner surfaces If this aspect is desired, it also presents an upper spray arm is seen to ensure even indoor application to articles places that have an upper opening and are of considerable height.

Such an application of successive films provides a homogeneous intimate contact of the entire outer surface with the Mattier solution, whereby this is treated simultaneously at the same time (because of the deviation of interference contacts that would be suitable, heterogeneities regarding the Reaction time and therefore the appearance achieved).

This facility in particular enables the preservation of decoration ration masks of the treated objects.

This facility is doubled by additional spray arms for Interior matting of certain objects that are specific to them (from Bare masks) can be used.

The relative arrangement of the additional spray arms enables that the outer films play the role of curtains, increasing the danger premature spraying of the articles to be treated with acid from the Spray arms is avoided.  

These films can be viewed as a linear and simply gravity flow of the matting solution through channels 24 transverse to the axis of the device, the amount dispensed being controlled by choice of strength and such that a continuous curtain is provided.

They can also be realized by flowing out along one Carrier made of synthetic fabric suitable for the emergence of a suitable Solution amount is suitable. The quantitative exit can under these Be conditions can be reduced compared to the first embodiment, wherein the required character of the perfect continuity of the liquid curtain remains. This variant is particularly interesting for the end elements of the treatment zone under consideration (prevention of outward spurt).

The characteristic treatment times for the two above The types of matting baths mentioned are very similar. The application of the bath lies in of the order of 20 to 35 seconds and the draining time after use at 60 to 90 sec.

The chemical attack continues during the draining. Its duration must therefore be limited to appropriate values, namely especially when objects with fragile masking compounds (e.g. alkaline-soluble) are treated, their resistance to Penetration decreases rapidly.

The neutralization implemented in unit 3 serves to

• - To stop the chemical attack and as such has to be done at the same time moderate simultaneous elimination of active substances on the lead treated surfaces;
• - Surfaces free of products attacking the glass such as ge formed fluorosilicates.

For this it is necessary to either use an acid rinse, which he allows new dissolution or a non-acidic rinse that but is mechanically active to reak the physical breakdown of absorbed capable gels and therefore enable their removal.

The latter measure consists of a certain sequence of flushing operations by spraying water of different qualities and be does not require the use of an additional acid solution as regards of the matting process is foreign and expensive to use and use.  

Therefore, neutral or non-neutral water is sprayed through the spray arms 27 , which is then passed to cleaning devices, and 29 rinsing water from the reservoir 34 is sprayed through the double spray arm 29 .

The rinses carried out in the unit 4 consist of rinsing with circulated water of approximately 50 ° C. (spray arms 32 ) and a final rinse with suitable cold water (spray arms 36 ), this water then being used to maintain a constant rinse water volume in the reservoir 34 .

The objects are discharged by the conveyor 15 at the end of the rinsing and conveyed close to the feed point.

The subdivision of the conveyor system for the objects into independent belts 5 for each unit makes it possible, on the one hand, to limit the losses of active substances, each lock floor 22, 26 practically recovering all of the substances that were used in the area of the corresponding conveyor 5 while, on the other hand, contamination outside the unit under consideration, in particular by the lower run of a single conveyor belt, which would also require the need for washing before returning to the loading point, is avoided.

Furthermore, the lateral arrangement of the Vorratsbehäl ter 21, 25, 34 easy maintenance, since the necessary work can be done without emptying the reactive liquids, simply by interrupting the return channels between the lock bottom and the storage container.

The device may also have other suitable means for covering the have objects to be treated with the matting bath.

Claims (10)

1. A process for the chemical matting of glassware, in particular lamp glasses, characterized in that the objects to be treated are continuously passed through a sealed tunnel and they are cleaned there one after the other by cleaning by spraying on a solution based on hydrofluoric acid followed by dripping followed by matting by covering the surfaces to be treated with a suitable solution based on hydrofluoric or hydrochloric acid by means of vertical liquid films through which the objects pass, followed by draining and then neutralization by spraying water followed by rinsing, subject also by spraying water. 2. The method according to claim 1, characterized in that the Bedec ken from spraying the matting solution, preferably from top to bottom and / or directed from the bottom upwards against the objects is. 3. Device for performing the method according to claim 1 or 2, characterized in that it comprises four successive units, a cleaning unit ( 1 ), a matting unit ( 2 ), a neutralizing unit ( 3 ) and a rinsing unit ( 4 ), which together are connected by sealed connection locks ( 10 ) and each have a sealed outer jacket ( 6 to 9 ), which is provided with means for access to the inside, has a horizontal conveyor ( 5 ) made of mesh belt, which is independent in the interior of the jacket is arranged so that it forms a conveyor path with the belts of the other units, which ensures the passage of the objects to be treated in a continuous manner in succession through the four units ( 1 to 4 ), means ( 17 a , 17 b ; 20 a , 20 b ; 29; 32; 36 ) for spraying and / or suitable covering, which are arranged in the interior of the jacket, has a lock bottom ( 22, 26, 31, 35 ) has, which is arranged under the jacket for collecting and removing or recirculating liquids inserted in the respective unit, and has protective curtains ( 23 ) on the inlet and outlet sides of the unit under consideration, the cleaning, matting and rinsing units ( 1, 2, 4 ) are laterally provided with storage / recycling containers ( 21, 25, 34 ) which are connected to the means for spraying and / or covering, while feed and discharge means ( 14, 15 ) for the treating objects are provided at the respective end of the sequence of units ( 1 to 4 ). 4. The device according to claim 3, characterized in that the cleaning unit Rei ( 1 ) contains only spray arms ( 17 a , 17 b ; 20 a ; 20 b) which are arranged above and below the plane of the upper run of the conveyor belt ( 5 ) of this unit and are provided with calibrated nozzles ( 18 ) directed towards the upper run. 5. Apparatus according to claim 3 or 4, characterized in that the matting unit ( 2 ) contains means for covering, which consist of several transverse channels ( 24 ) which are arranged above the upper run of the conveyor belt ( 5 ) of this unit and vertical Generate films or curtains from matting solution perpendicular to the conveying direction of the objects to be treated, the amount of discharge from the channels ( 24 ) being adjustable. 6. The device according to claim 5, characterized in that the mat animal unit ( 2 ) contains means for covering, which are formed by carriers made of suitable synthetic fabric, which are suspended from the channels ( 24 ) and along which the films are made Drain the matting solution under the influence of gravity. 7. Apparatus according to claim 5 or 6, characterized in that the matting device ( 2 ) additionally has upper and lower spray arms for mat animal solution, which are arranged above and below the upper run of the conveyor belt ( 5 ) of this unit and are provided with calibrated nozzles, which are aimed at the upper run. 8. Device according to one of claims 3 to 7, characterized in that the neutralization and rinsing units ( 3, 4 ) have upper and un lower water spray arms ( 27, 29, 32, 36 ) above and below the upper run of the conveyor belt ( 5 ) of the respective unit ( 3, 4 ) and are provided with calibrated nozzles which are directed towards the upper run. 9. Device according to one of claims 3 to 8, characterized in that the conveyor belt ( 15 ) of the rinsing unit ( 4 ) is extended to the outside as a discharge conveyor and is arranged with its removal end in the immediate vicinity of the charging belt ( 14 ) which is located on Entry of the cleaning unit ( 1 ) is located. 10. Device according to one of claims 3 to 9, characterized in that the two ends of the sequence of units ( 1 to 4 ) of an entry and exit boxes ( 12 ) are formed, are subjected to a vacuum by suction devices ( 13 ) and with protective curtains at the entrance and exit of the treatment tunnel formed by these units ( 1 to 4 ).